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arXiv · 0706.1620

High-quality all-oxide Schottky junctions fabricated on heavily Nb-doped SrTiO3 substrates

A. Ruotolo·C. Y. Lam·W. F. Cheng·K. H. Wong·C. W. Leung
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Abstract

We present a detailed investigation of the electrical properties of epitaxial La0.7Sr0.3MnO3/SrTi0.98Nb0.02O3 Schottky junctions. A fabrication process that allows reduction of the junction dimensions to current electronic device size has been employed. A heavily doped semiconductor has been used as a substrate in order to suppress its series resistance. We show that, unlike standard semiconductors, high-quality oxide-based Schottky junctions maintain a highly rectifying behavior for doping concentration of the semiconductor larger than 10^20 cm^(-3). Moreover, the junctions show hysteretic current-voltage characteristics.

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A. Ruotolo, C. Y. Lam, W. F. Cheng, K. H. Wong, C. W. Leung. 2007-06-15. High-quality all-oxide Schottky junctions fabricated on heavily Nb-doped SrTiO3 substrates. https://doi.org/10.1103/physrevb.76.075122

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